Photographic colour material

ABSTRACT

Light-sensitive silver halide color emulsions are described which comprise a cyan-forming color coupler of the formula :   WHEREIN : Z represents the atoms necessary to close a fused-on benzene or tetrahydrobenzene ring, Y represents hydrogen or a substituent conferring to the color coupler a 2-equivalent character, R1 represents a straight-chain C1-C5 alkyl group or an aryl group with electron-withdrawing substituent, R2 represents a straight-chain C1-C5 alkyl group, or R2 together with R1 represents the atoms necessary to close a cycloaliphatic ring, and R3 stands for a diffusion-fast making straight-chain acyclic aliphatic hydrocarbon group comprising from 10 to about 20 Catoms or for a residue substituted by a diffusion-fast making acyclic aliphatic hydrocarbon group having from 10 to about 20 C-atoms, or R3 together with R1 represents the atoms necessary to complete a diffusion fast making cycloaliphatic hydrocarbon group which comprises in the ring or together with the C-atoms of an alkyl substituent on the ring at least 12 C-atoms. Upon exposure and color development, cyan dyestuff images are formed in the described emulsions which have favorable spectral properties and a high stability against heat.

United States Patent [191 Vanden Eynde et a1.

[451 Oct. 2, 1973 1 PHOTOGRAPHIC COLOUR MATERIAL [75] Inventors: Hector Alfons Vanden Eynde,

Edegem; Raphael Karel Van Poucke, Berchem; Arthur Henri De Cat, Mortsel; Gaston Jacob Benoy, Edegem, all of Belgium [73] Assignee: Gevaert-AGFA N.V., Mortsel,

Belgium {22] Filed: Feb. 8, 1971 [21] Appl. No.: 113,647

Primary ExaminerJ. Travis Brown Art0rney-Brufsky, Staas, Breiner & Halsey [57] ABSTRACT Light-sensitive silver halide color emulsions are described which comprise a cyan-formingcolor coupler of the formula wherein Z represents the atoms necessary to close a fused-on benzene or tetrahydrobenzene ring,

Y represents hydrogen or a substituent conferring to the color coupler a 2-equivalent character,

R represents a straight-chain C,C alkyl group or an aryl group with electron-withdrawing substituent,

R represents a straight-chain C -C alkyl group, or R together with R represents the atoms necessary to close a cycloaliphatic ring, and

R stands for a diffusion-fast making straight-chain acyclic aliphatic hydrocarbon group comprising from 10 to about 20 C-atoms or for a residue substituted by a diffusion-fast making acyclic aliphatic hydrocarbon group having from 10 to about 20 C-atoms, or R together with R represents the atoms necessary to complete a diffusion fast making cycloaliphatic hydrocarbon group which comprises in the ring or together with the C-atoms of an alkyl substituent on the ring at least 12 C-atoms. Upon exposure and color development, cyan dyestuff images are formed in the described emulsions which have favorable spectral properties and a high stability against heat.

9 Claims, No Drawings PHOTOGRAPHIC COLOUR MATERIAL This invention relates to novel cyan forming colour couplers, to the use thereof in the production of photographic colour images and to photographic material containing such colour couplers.

It is known that for the production of a photograhic colour image in a light-sensitive silver halide layer, the exposed silver halide is developed to a silver image by means of an aromatic primary amino compound in the presence of a colour coupler which reacts with the oxidized developing substance to form a dyestuff on the areas corresponding to the silver image.

In the subtractive three-colour photography a lightsensitive photographic colour material is used containing a red-sensitized, a green-sensitized and a bluesensitive silver halide emulsion layer wherein on colour development, by the use of appropriate colour couplers, a cyan, magenta and yellow dyestuff image are formed respectively.

The colour couplers may be added directly to the developer solution or they can be incorporated in the photographic material. In the latter case, it is required that the colour couplers do not wander or diffuse through the emulsion from their original site. For this purpose the colour couplers are usually provided in their molecule with one or more ballast groups, e.g. a long chain aliphatic groupsuch as an alkyl group containing from 12 to C-atoms in straight line. This ballast group imparts to the molecule a hydrophobic character and holds the component firmly in its original site.

Various methods have been described to incorporate these non-diffusing colour couplers into hydrophilic colloid compositions;

A method commonly employed to incorporate the non-diffusing colour couplers into hydrophilic colloid compositions such as a gelatino silver halide emulsion is to provide in the molecule of said couplers in addition to the ballasting group one or more salt-forming groups more particularly carboxy and/or sulpho groups so that the couplers can be dissolved in the hydrophilic colloid composition in the form of their soluble alkali metal salts.

Alternate methods of incorporating non-diffusing colour couplers in hydrophilic colloid compositions make use of dispersion techniques.

According to one such method, e.g. as described in German Patent Specification 1,127,714 waterinsoluble colour couplers are dissolved in low-boiling substantially water-immiscible solvents such as ethyl acetate, methylene chloride, chloroform, etc. whereupon the solution formed is dispersed in extremely fine droplets in the presence of a wetting agent into the hydrophilic colloid medium after which the solvent is removed by evaporation, leaving behind a dispersion of colour coupler distributed throughout the hydrophilic colloid composition.

Another process for dispersing non-diffusing colour couplers in photographic hydrophilic colloid compositions is described in U.S. Pat. No. 2,322,027. According to this process a colour coupler is dissolved in a high-boiling oily solvent such as tricresyl phosphate and di-n-butyl-phthalate whereupon the resulting solution is dispersed in the form of extremely fine droplets in the hydrophilic colloid composition, the oily solvent being left in the said composition.

In preparing silver halide emulsions comprising nondiffusing colour couplers by the use of dispersion techniques various difficulties are encountered. Indeed, colour couplers that are intended to be incorporated into photographic colloid media from solutions in lowboiling or high-boiling organic solvents should have a sufficient solubility in said solvents and be homogeneously distributed through the said colloid media before as well as after coating to form a hydrophilic colloid layer of a photographic multilayer colour material so that no crystallization of the colour coupler occurs. This condition limits the number of colour couplers suitable for such applications.

In U.S. Pat. No. 3,005,709 l-hydroxy-Z-naphthamide colour couplers for cyan have been disclosed in which the amide group is derived from highly branched tertiary alkyl amines. In order to be perfectly nondiffusible in hydrophilic colloid media highly branched tertiary alkyl amines sold under the trade name Primene SM-T" by the Rohm and Haas Company, Philadelphia, Pennsylvania, U.S.A. are used in the preparation of the l-hydroxy-2-naphthamide colour couplers. Though these non-diffusing cyan-forming colour couplers have high solubility in oily type organic solvents and high resistance to crystallization so that they are very suitable for being incorporated into photographic colloid media by means of the above dispersion techniques, they show the disadvantage of yielding upon colour development with an aromatic primary amino colour developing agent dyes with unreproducible spectral and sensitometric characteristics and too low a maximum density.

It is an object of the present invention to provide cyan-forming colour couplers which do not diffuse from one hydrophilic colloid layer into another when incorporated in a multilayer colour material.

A further object of the present invention is to provide l-hydroXy-Z-naphthamide cyan-forming colour couplers in which the amide group is derived from amines with tertiary a-carbon atoms which yield upon colour development dyes with reproducible spectral and sensitometric characteristics.

wherein Z represents the atoms necessary to close a fused-on benzene or tetrahydrobenzene ring,

Y represents hydrogen or a substituent which confers to the colour coupler a Z-equivalent character such as halogen e.g. chlorine and bromine, sulpho in acid or salt form, azo such as phenylazo and substituted phenylazo, the group SR wherein R stands for alkyl, aryl or a heterocycle, etc.

R represents a straight-chain C,-C,, alkyl such as methyl, ethyl, and propyl or an aryl group with electron-withdrawing substituent for example mchlorophenyl,

R represents a straight-chain C C,, alkyl such as methyl, ethyl and propyl, or

R together with R represent the atoms necessary to close a cycle-aliphatic ring e.g., cyclohexyl, and

R represents a straight-chain acyclic aliphatic hydrocarbon group with from to about 20 C-atoms which renders the molecule fast to diffusion in photographic hydrophilic colloid media or a residue comprising a diffusion-fast making acyclic aliphatic hydrocarbon group such as the residues X,D and -Cl-l -X -D wherein D stands for an acyclic aliphatic hydrocarbon group with from 10 to about 20 C-atoms, X stands for COO, 4).

R being hydrogen or C,C alkyl and Y being a chemical bond, oxygen, sulphur, sulphonyl, NHCO, CONH, NHSO or SQ NH, and X stands for -N(R- sulphur, CON(R COO-,

@ or CON-(RO-Q R and Y having the same significance as above, or

R together with R represent the atoms necessary to complete a diffusion fast-making cycloaliphatic hydrocarbon group which comprises in the ring or together with the C-atoms of an alkyl substituent on the ring at least 12 C-atoms.

The novel cyan-forming colour couplers according to the present invention were not only found to be very suitable for being incorporated into photographic hydrophilic colloid media by means of dispersion techniques in that they have a high solubility in the organic solvents used therefor but it was also found that they yield dyes which possess besides favourable spectral properties an excellent stability against heat.

The following compounds are representative colour couplers corresponding to the above general formula I CHa 0 ONH-(tl-(CHDnCl-la CH3 CONE-- cz r 911 3 Cgllb The preparations given hereinafter illustrate how the colour couplers according to the present invention can be prepared.

Preparation 1 Colour coupler l a. a,a-dimethylhexadecylalcohol 355 g of methyl iodide were dissolved in 625 ml of anhydrous diethyl ether. Some drops of this solution were added to 60 g of magnesium in 250 ml of anhydrous diethyl ether thus starting an exothermic reaction which caused the ether to boil. The remaining methyl iodide solution was then added dropwise at such a rate that the reaction mixture kept on refluxing. When all of the methyl iodide solution was added, the mixture was boiled for 2 hours on a water-bath.

Then a solution of 270 g of methyl palmitate in 1 litre of anhydrous diethyl ether was added dropwise in such a way that by the exothermic reaction the refluxing continued. The mixture was further refluxed for 2 hours on a hot water bath whereupon the reaction mixture was poured with stirring into a solution of 250 g of ammonium chloride in 3 litres of ice-water.

The ether was washed with water and dried. The ether was evaporated leaving the a,a-dimethylhexadecylalcohol.

Yield 263 g (97.5 percent).

Melting point 39C.

b. apt-dimethylhexadecylamine To 170 ml of acetic acid, 35 g of sodium cyanide were added portionwise taking care, that the temperature is kept below 20C by external cooling. Then, a

'mixture of ml of acetic acid and 92 ml of concentrated sulphuric acid was added dropwise while keeping the temperature below 20C.

180 g of mot-dimethylhexadecylalcohol were added to the reaction mixture in 30 minutes with stirring but without cooling. The temperature rose to 50C. Stirring was continued for minutes and the reaction mixture was left standing overnight at room temperature. Then the mixture was poured into 1,200 ml of ice-water and the product that separated was filtered, washed with water and filtered again with suction.

The moist product was dissolved in 1,680 ml of ethanol and, after addition of 500 ml of 10 N sodium hydroxide, the mixture was refluxed with stirring for 2 V1 hours. The ethanol was evaporated and the residue extracted with ether. The ether layer was washed, dried and concentrated by evaporation. The oily residue was subjected to fractional destillation. Yield g (86 percent) of a colourless liquid with a boiling point ll6-l 18C/0.25 mm.

c. N-(a,adimethylhexadecyl)-l-hydroxy-4-chloro-2- naphthamide (compound 1) 123 g of a,a-dimethylhexadecylamine and 136.5 g of phenyl-1-hydroxy-4-chloro-2-naphthoate were heated with stirring for 2 hours on an oil-bath of 155-l60C. The phenol formed was distilled off under reduced pressure whereupon the residue was recrystallized from 800 ml of ethanol.

Yield g (78.5 percent).

Melting point 61C.

Preparation 2 Colour coupler 2 Colour coupler 2 was prepared in a similar way as colour coupler 1 from phenyl l-hydroxy-2-naphthoate and a,a-dimethyl-hexadecylamine.

Yield 1 83 percent.

Melting point 51C.

Preparation 3 Colour coupler 3 81 g of l-hydroxy-4-fluorosulphonyl-Z-naphthoix acid and 270 ml of thionyl chloride were heated with stirring for 4 hours on a boiling water-bath. The excess of thionyl chloride was removed by evaporation under reduced pressure and the residue was redissolved in 400 ml of anhydrous toluene. This solution was then' added dropwise to a solution of 80.5 g of a,a-dimethylhexadecylamine and 41.6 ml of triethylamine in 200 ml of anhydrous toluene.

The reaction mixture was refluxed for 4 hours with stirring and the triethylamine hydrochloride formed was filtered off by suction. Then the toluene was removed from the filtrate by evaporation under reduced pressure.

The residue was dissolved in 800 ml of acetone and 240 ml of 5N potassium hydroxide was added, whcreupon the whole was refluxed with stirring for 3 hours. After addition of another 24 ml of 5N potassium hydroxide refluxing is continued for 2 hours. To the hot solution, 150 ml of glacial acetic acid were added dropwise in 5 minutes and the mixture is then left to cool.

The underlying aqueous layer was removed and the supernatant layer was concentrated by evaporation under reduced pressure. The residue was recrystallized from 600 ml of methanol. The product was further purified by boiling again in 300 ml of methanol. After cooling, the product is filtered off by suction and dried.

Yield 95 g(57 percent).

Melting point C.

Preparation 4 Colour coupler 4 Colour coupler 4 was prepared in a similar way as colour coupler 1 from phenyl 5,6,7,8-tetrahydro-lhydroxy-4-chloro-2-naphthoate and a,a-dimethylhexadecylamine.

Yield 65 percent.

Melting point 34C.

Preparation 5 1 Colour coupler 5 Colour coupler 5 was prepared in a similar way as colour coupler 1 from phenyl l-hydroxy-4-chloro-2- naphthoate and a,a-diethylhexadecylamine.

Yield 91 percent.

The a,a-diethylhexadecylamine was prepared in a similar way as a,u-dimethylhexadecylamine from a,a-diethylhexadecylalcohol.

Yield 76 percent.

Boiling point 135l40C/0.2 mm.

The a,a-diethylhexadecylalcohol was prepared in a similar way as a,a-dimethylhexadecylalcohol from ethyl iodide, magnesium and methyl palmitate.

Yield 97 percent.

Melting point 33C.

Preparation 6 Colour Coupler 6 Colour coupler 6 was prepared in a similar way as colour coupler 1 from phenyl 1-hydroxy-4-chloro-2- naphthoate and a,a-di-n-propyloctadecylamine.

Yield 80 percent.

The a,a-di-n-propyloctadecylamine was prepared in a similar way as a,a-dimethylhexadecylamine from a,a-di-n-propyloctadecyl-alcohol.

Yield 60 percent.

Boiling point 155-160C/0.15 mm.

The a,a-di-n-propy1octadecylalcohol was prepared in a similar way as a,a-dimethylhexadecylalcohol from n-propyliodide, magnesium and methyl stearate.

Yield 95 percent.

Melting point 30C.

Preparation 7 Colour coupler 7 a. Methyl a-(1-hydroxy-4-chloro-2- naphthoylamino)isobutyrate 95.5 g of methyl a-aminoisobutyrate, prepared as described in Tetrahedron 11, 43-44 (1960), starting from a-aminoisobutyric acid which is commercially available from the firm Dr.Th.Schuchardt Munich, W.Germany, and 243.5 g of phenyl 1-hydroxy-4-chloro-2-naphthoate were heated with stirring on an oil bath for 2 hours at 130C and then for 2 hours at 155-160C.

The reaction mixture was recrystallized from 1 litre of cyclohexane.

Yield 172.5 g (66 percent).

Melting point 159.160C.

b. a-(1-hydroxy-4-chloro-2-naphthoylamino)- isobutyric acid 160.75 g of the above isobutyrate in 1 litre of N sodium hydroxide were heated with stirring to the boiling temperature. After approximately 10 minutes a solution was obtained which was then cooled in an ice-bath and to which was added dropwise with stirring 100 ml of concentrated hydrochloric acid.

The precipitate formed was filtered by suction, washed with water and while moist recrystallized from 350 ml of methanol.

Yield 149 g (97 percent).

Melting point 189C.

0. N-dodecyloxypropyl-a-(1-hydroxy-4-chloro-2- naphthoylamino) isobutyramide 15.4 g of the above isobutyric acid were dissolved in 50 ml of anhydrous acetonitrile whereupon 12.2 g of dodecyloxypropylamine, commercially available from the firm Dr.Th.Schuchardt, Munich, W.Germany. were added with stirring. At a temperature of approximately 20C, 1 1.3 g of dicyclohexylcarbodiimide, which is also commercially available from the above firm, were added dropwise whereby the temperature of the reaction mixture rose to 42C. Stirring was continued for 1 hour whereupon the mixture was refluxed for 10 minutes. The dicyclohexylurea formed was filtered off and the product that crystallized in the filtrate was isolated and washed with acetonitrile.

Yield 23 g (86.5 percent).

Melting point 67C.

Preparation 8 Colour coupler 8 N-methyl-N-octadecyl-a-( l-hydroxy-4-chloro-2- naphthoylamino)-isobutyramide was prepared in a similar way as colour coupler 7 starting from N-methyl-N- octadecylamine, a-( l-hydroxy-4chloro-2- naphthoylamino) isobutyric acid and dicyclohexylcarbodiimide.

Yield percent.

Melting point 7072C.

Preparation 9 Colour coupler 9 a. ethyl }3-(1-hydroxy-4-ch1oro-2-naphthoylamino)- isovalerate 65 g of ethyl fl-amino-isovaierate, prepared as described in Ann. 661, 111 (1963), and 134 g of phenyl 1-hydroxy-4-chloro-2-naphthoate were heated with stirring on an oil bath for 2 hours at 135-140C and then for 2 hours at C.

The phenol formed was distilled off under reduced pressure and the residue was recrystallized from 300 m1 of ethanol.

Yield 119 g (76 percent).

Melting point 103C.

b. B-(1-hydroxy-4-chloro-2-naphthoylamino)- isovaleric acid 116 g of the above isovalerate in 700 ml of N sodium hydroxide were heated with stirring at the boiling temperature whereby a solution formed. Heating was continued for 10 min. and the solution was then cooled in an ice-bath. Concentrated hydrochloric acid was added dropwise and the precipitate formed was isolated and washed with water. The product was stirred in 100 ml of methanol, filtered by suction and recrystallized from 320 ml of acetonitrile.

Yield 82 g (76.5 percent).

Melting point 172174C.

c. N-(o-hexadecyloxyphenyl) B-(1-hydroxy-4-chloro- 2-naphthoylamino)isovaleramide 17.7 g of the above isovaleric acid were dissolved in 60 ml of anhydrous acetonitrile and 18.8 g of ohexadecyloxyaniline were added with stirring. 13.2 g of dicyclohexylcarbodiimide were added dropwise at room-temperature whereby an exothermic reaction started; stirring was continued for 1 hour whereupon the mixture was refluxed for 10 minutes. The dicyclohexylurea formed was filtered off and to the hot filtrate methylene chloride was added in such an amount that the oily precipitate dissolved. The white product that crystallized was fitered off by suction, washed with methanol and dried.

Yield 28.3 g (81 percent).

Melting point 90C.

Preparation 10 Colour coupler 10 N-methyl-N-octadecyl B-(1-hydroxy-4-chloro-2- naphthoylamino) isovaleramide was prepared in a similar way as colour coupler 9 from N-methyl-N- 9 octadecylamine, [3-(l-hydroxy-4-chloro-2-naphthoylamino)-isovaleric acid and dicyclohexylcarbodiimide.

Yield 82.5 percent.

Melting point 57C.

Preparation ll :Colour coupler ll This colour coupler was prepared in a similar way as colour coupler 1 from phenyl l-hydroxy-4-chloro-2- naphthoate and a,a-diethyldocosylamine.,

Yield 85 percent.

Melting point 44C.

The a,a-diethyldocosylamine was prepared in a similar way as m-dodecyloxya-methyl-aethylbenzylamine and preparation of which is given hereinafter, from a,a-diethyldocosylalcohol.

Yield 82 percent.

Melting point 26C.

The a,a-diethyldocosylalcohol was prepared in a' similar way as a,a-dimethylhexadecylalcohol ethyl iodide, magnesium, and methylbehenate.

Yield 97 percent.

Melting point 52C.

Methyl behenate was prepared from behenic acid, sulphurous oxychloride and methyl alcohol.

Yield 96 percent.

Melting point 5 l-52C.

Preparation 12 Colour coupler 12 This colour coupler was prepared in a similar way as colour coupler 9 from -y-lauryloxy-propylamine, B-( lhydroxy-4-chloro-2-naphthoylamino)-isovaleric acid and dicyclohexylbarbodiimide.

Yield 57 percent.

Preparation 13 2 Colour coupler 13 This colour coupler was prepared in a similar way as colour coupler I from phenyl l-hydroxy-4-chloro-2- napthhoate and a-methyl-a-ethyl-octadecylamine.

Yield 83 percent.

Melting point 55C.

The a-methyl-a-ethyloctadecylamine was prepared in a similar way as a,a-dimethylhexadecylamine from a-methyl-a-ethyloctadecyl alcohol.

Yield 50 percent.

The a-methyl-a-ethyloctadecylalcohol was prepared asfollows To the Grignard solution prepared in a similar way as in preparation Ia) from 60 g of magnesium, 390 g of ethyliodide and 875 ml diethylether, a solution of 562 g of methyl heptadecyl ketone was added in such a way that refluxing continued due to the exothermic reaction. The mixture was further refluxed for 2 hours on a hot water bath whereupon the reaction mixture was poured with stirring into a solution of 500 g of ammonium chloride in 5 litres of ice-water. The ether solution was washed with water and dried. The ether was then removed by evaporation leaving a residue of a-methyl-a-ethyloctadecylalcohol.

Yield 94 percent.

Preparation 14 Colour coupler 14 a. m-dodecyloxy-a-methyl-a-ethylbenz'ylalcohol To the Grignard solution prepaed in a similar way as in preparation 1.0) from 30 g of magnesium, 195 g of ethyl iodide and 300ml of diethylether, a solution of 304 g of m-dodecyloxyacetophenone in 1250 ml of diethylether was added in such a way that refluxing continued due to the exothermic reaction. When all was added, refluxing was continued for 2 hours, whereupon the mixtured was poured with stirring into a solution of 250 g of ammonium chloride in 2.5 litres of ice-water.

The ether layer was washed with water and dried. The ether was removed by evaporation leaving a residue of m-dodecyloxy-a-methyl-a-ethylbenzylalcohol.

Yield 96.5 percent.

b. m-dodecyloxy-a-methyl-a-ethylbenzylamine 267.5 g of the above alcohol and 98 g of sodium cyanide were stirred at 40C in 600 ml of n-dibutylether. Then 240 ml of 95 percent sulphuric acid was added dropwise in such a way that the temperature is kept at 4045C by the exothermic reaction. Stirring was then continued for 2 hours on a water-bath of 50C.

600 ml of n-butanol were added to the reaction mixture whereupon the mixture was refluxed for 2 hours with stirring. The mixture was made strongly alkaline by addition of 5N sodium hydroxide whereupon the organic layer was separated, washed with water and concentrated by evaporation till dry. The crude reaction product was purified by turning into the oxalate in a mixture of diethylether and-methanol. The oxalate was filtered off whereupon by addition of alkali in isopropylether the m-dodecyloxy-a-methyl-aethylbenzylamine was set free.

Yield 45 percent.

Melting point 122C.

0. Colour coupler l4 This'colour coupler was prepared in a similar way as colour coupler 1 from phenyl l-lhydroxy-4-chloro-2- naphthoate and m-dodecyloxy-a-methyl-aethylbenzylamine.

Yield 82 percent.

Preparation 15: Colour coupler 15 p a. B-dodecylthio-a,a-dimethylpropionic acid 157 g of chloropivalic acid, 232 g of dodecylmercaptan and 151 g of 85 percent potassium hydroxide were refluxed for 3 hours with stirring in 1 litre of ethylene glycol monomethylether. The mixture was then poured into a mixture of 1 litre of ice-water and 500 ml of concentrated hydrochloric acid. The product formed was extracted with diethylether and washed acid free with water. The ether layer was dried and concentrated by evaporation till dry. r

The crude product was subjected to fractional distillation.

Yield 230 g (66 percent).

Boiling point l77l78C/O.3 mm b. B-dodecylthio-a,a-dimethylethylamine 75 g of the above compound and 250 ml of dry benzene were stirred and 227 ml of percent suplhuric acid were added. The mixture was heated to 45C whereupon 18 g of sodium azide were added portionwise in 1 hour so that the temperature was kept at 4550C by the exothermic reaction. The mixture was further heated on a water bath of 50C until all gas evolution ceased.

The underlying acid layer was separated and poured with stirring into 1 litre of ice-water. The white precipitate was filtered off and washed with water. The product was set free from its sulphate form by'addition of aqueous alkali in methylene chloride. The methylene chloride layer was freed from alkali by washing with water, dried and concentrated by evaporation till dry.

The crude product was recrystallized from cyclohexan.

Yield 40 g (59 percent).

Melting point 86C.

c. Colour coupler l5 This colour coupler was prepared in a similar way as colour coupler 1 from phenyl l-hydroxy-2-naphthoate and B-dodecylthio-a,a-dimethylethylamine.

Yield 74 percent.

Preparation 16 Colour coupler 16 a. a-ethylcyclododecylalcohol To the Grignard solution prepared in a similar way as in preparation la) from 30 g of magnesium, 195 g of ethyl iodide and 300 ml of diethylether, a solution of 182 g of cyclododecanone in 1 litre of diethylether was added in such a way that the mixture continues to reflux by the exothermic reaction. Refluxing was then continued for 2 hours whereupon the mixture was poured with stirring into a solution of 250 g of ammonium chloride in 2.6 litres of ice-water. The ether layer was washed with water and dried. The ether was removed by evaporation leaving tat-ethylcyclododecylalcohol.

Yield 202 g (95 percent).

Melting point 28C.

b. N-formyl-a-ethylcyclododecylamine To a mixture of 106 g of the above compound and 61.3 g of sodium cyanide in 325 ml of n-dibutylether, 150 ml of 95 percent sulphuric acid were added dropwise with stirring at a temperature of 40-45C in such a way that the temperature is kept at 40-45 percent by the exothermic reaction. Stirring is continued for 2 hours on a water-bath of 5055C whereupon the mixture is poured with stirring into 500 ml of ice-water. The ether layer was separated and washed acid free by means of luke water. In the ether layer, N-fonnyl-aethylcyclododecylamine crystallized in the form of a white product.

Melting point 9698C.

Yield 2 90 g (75.5 percent).

c. zit-ethylcyclododecylamine 47.8 g of the above compound was refluxed for 2 hours with stirring in 280 ml of ethyleneglycol monomethyl ether and 40 ml of concentrated hydrochloric acid. The reaction mixture was then poured into a solution of 280 ml of water and 55 ml of lON sodium hydroxide. The product was extracted with ether and the ether layer was dried and concentrated by evaporation. The residue was distilled. A colourless, little viscous liquid .was obtained which had a boiling point of l02-l07C/0.5 mm.

Yield 34.2 g (81 percent).

d. Colour coupler 16 This colour coupler was prepared in a similar way as colour coupler 1 from phenyl 1-hydroxy-4-chloro-2- naphthoate and a-ethyl-cyclododecylamine.

Yield 80 percent.

Melting point l69l70C.

Preparation 17 Colour coupler 17 a. a-dodecylcyclohexylalcohol To the Grignard solution prepared in a similar way as in preparation La) from 24 g of magnesium, 249 g of dodecylbromide and 1 litre ofdiethylether, 184 g of anhydrous magnesium bromide were added. Then, 147 g of cyclohexanone was dropwise added in 30 min. so that refluxing continued by the exothermic reaction. Refluxing of the mixture continued for 2.5 hours whereupon it was poured into a solution of 400 g of ammonium chloride in 3 litres of ice-water. The ether layer was washed with water and dried. The ether was evaporated and the residue subjected to fractional distillation. A colourlessliquid was obtained.

Boiling point 135l37C/0.03 mm. Yield 130 g (48.5 percent). b. a-dodecylcyclohexylamine 26.8 g of the above compound and 7.35 g of sodium cyamide in ml of n-dibutylether were stirred at 50C. Then 24.4 ml of 95 percent sulphuric acid were added dropwise in 1.5 hour so that the temperature of the reaction mixture was kept at 5055C. Stirring was continued for 30 min. at 5055C.

75 ml of n-butanol were added to the reaction mixture whereupon the whole was refluxed for 1.5 hour with stirring. The reaction mixture was made strongly alkaline by addition of 5N sodium hydroxide.

The organic layer was separated, washed alkali free with water and concentrated by evaporation till dry.

Yield 24.1 g percent).

c. Colour coupler 17 This colour coupler was prepared in a similar way as colour coupler 1 from phenyl l-hydroxy-Z-naphthoate and a-dodecylcyclohexylamine.

Yield 90 percent.

Melting point 53C.

For preparing a usable photographic multilayer colour material the non-diffusing colour couplers for each colour separation image are usually incorporated into the coating compositions of the differently sensitized silver halide emulsion layers. However, the nondiffusing colour couplers may also be added to the coating compositions of non-light-sensitive colloid layers which are in water-permeable relationship with the light-sensitive silver halide emulsion layers.

The cyan-forming colour couplers of the present invention are preferably incorporated into photographic hydrophilic colloid media from solutions in highboiling sparingly water-miscible solvents such as di-nbutyl phthalate and tricresyl phosphate or in lowboiling sparingly water-miscible solvents such as ethylacetate, methylene chloride and chloroform, etc. or mixtures thereof in that they have a high solubility therein and very fine dispersions in hydrophilic colloid media can be obtained by means of these solvents. For this purpose these solutions are dispersed in extremely fine droplets, preferably in the presence of a wetting or dispersing agent into the hydrophilic colloid medium, the low-boiling sparingly water-miscible solvent then being removed by evaporation. Of course the compounds of the invention can also be incorporated into the hydrophilic colloid media in other ways. Any technique known by those skilled in the art for incorporating colour couplers, into colloid compositions can be used. For instance, the water-soluble colour couplers i.e. those containing a water-solubilizing sulpho group (Y SO H), is acid or salt form can be incorporated into the coating composition of the layer in question from an aqueous solution. When the compound can be liquefied by slight heating or when it is a liquid at room temperature the liquid can be dispersed as such in the hydrophilic colloid composition.

The hydrophilic colloid composition into which the compounds of the invention are dispersed or dissolved need not necessarily be the coating composition itself of the hydrophilic colloid layer such as a silver halide emulsion layer into which the compounds are intended to be present. The compounds may advantageously be first dispersed or dissolved in an aqueous non-lightsensitive hydrophilic colloid solution whereupon the resultant mixture, after the occasional removal of the organic solvents employed, is intimately mixed with the said coating composition of the light-sensitive silver halide emulsion layer or other water-permeable layer just before coating.

For more details about particularly suitable techniques that may be employed for incorporating the colour couplers of the invention into a hydrophilic colloid layer of a photographic material there can be referred to e.g., U.S. Pat. Nos. 2,269,158 2,284,887 2,304,939 2,304,940 and 2,322,027, United Kingdom Pat. Nos. 791,219 1,098,594 1,099,414 1,099,415 1,099,416 and 1,099,417, French Pat. No. 1,555,663, Belgian Pat. No. 722,026, German Pat. No. 1,127,714 and to United Kingdom Pat. application No. 14,763/69.

The couplers according to the invention may be used in conjunction with various kinds of photographic emulsions. Various silver salts may be used as the sensitive salt such as silver bromide, silver iodide, silver chloride or mixed silver halides such as silver chlorobromide, silver bromoiodide and silver chlorobromoiodide. The couplers can be used in emulsions of the mixed packet type as described in U.S. Pat. No. 2,698,794 or emulsions of the mixed grain type as described in U.S. Pat. No. 2,592,243. The colour couplers can be used with emulsions wherein latent images are formed predominantly on the surface of the silver ha lide crystal, or with emulsions wherein latent images are formed predominantly inside the silver halide crystal.

The hydrophilic colloid used as the vehicle for the silver halide may be, for example, gelatin, colloidal albumin, zein, casein, a cellulose derivative, a synthetic hydrophilic colloid such as polyvinyl alcohol, poly-N- vinyl pyrrolidone, etc. if desired, compatible mixtures of two or more of these colloids may be employed for dispersing the silver halide.

The light'sensitive silver halide emulsions of use in the preparation of a photographic material according to the present invention may be chemically as well as optically sensitized. They may be chemically sensitized by effecting the ripening in the presence of small amounts of sulphur containing compounds such as allyl thiocyanate, allyl thiourea, sodium thiosulphate, etc. The emulsions may also be sensitized by means of reductors for instance tin compounds as described in French Pat. No. 1,146,955 and in Belgian Pat. No. 568,687, iminoamino methane sulphinic acid compounds as described in United Kingdom Pat. No. 789,823 and small amounts of noble metal compounds such as gold, platinum, palladium, iridium, ruthenium and rhodium compounds. They may be optically sensitized by means of cyanine and merocyanine dyes.

The said emulsions may also comprise compounds which sensitize the emulsions by development accelerationfor example compounds of the polyoxyalkylene type such as alkylene oxide condensation products as described among others in U.S. Pat. Nos. 2,531,832 2,533,990 3,210,191 and 3,158,484, in United Kingdom Pat. Nos. 920,637 and 991,608 and in Belgian Pat. No. 648,710 and onium derivatives of amino-N-oxides as described in United Kingdom Pat. No. 1,121,696.

Further, the emulsions may comprise stabilizers e.g. heterocyclic nitrogen-containing thioxo compounds such as benzothiazoline-Z-thione and 1-phenyl-2-tetrazoline-S-thione and compounds of the hydroxytriazolopyrimidine type. They can also be stabilized with mercury compounds such as the mercury compounds described in Belgian Pat. No. 524,121 677,337 and 707,386 and in U.S. Pat. No. 3,179,520.

The light-sensitive emulsions may also comprise all other kinds of ingredients such as plasticizers, hardening agents, wetting agents, etc.

The non-diffusing cyan colour formers described in the present invention are usually incorporated into the redsensitized silver halide emulsion for forming one of the differently sensitized silver halid emulsion layers of a photographic multilayer colour material. Such photographic multilayer colour material usually comprises a support, a red-sensitized silver halide emulsion layer with a cyan colour former, a green-sensitized silver halide emulsion layer with a magenta colour former and a blue-sensitive silver halide emulsion layer with a yellow colour former.

The emulsions can be coated on a wide variety of photographic emulsion supports. Typical supports include cellulose ester film, polyvinylacetal film, polystyrene film, polyethylene terephthalate film and related films or resinous materials, as well as paper and glass.

For the production of photographic colour images according to the present invention an exposed silver halide emulsion layer is developed with an aromatic primary amino developing substance in the presence of a colour coupler according to the present invention. All colour developing agents capable of forming azomethine dyes can be utilised as developers. Suitable developing agents are aromatic compounds such as pphenylene diamine and derivatives for example N,N-dialkyl-p-phenylene diamines such as N,N-diethylp-phenylene diamine, N,N-dialkyl-N'-sulphomethyl-pphenylene diamines, and N,N-dialkylN'- carboxymethyl-p-phenylene diamines.

The following examples illustrate the present invention.

EXAMPLE 1 A 5 percent aqueous solution of gelatin having dispersed therein per litre 50 g of colour coupler 7, was prepared by dispersing by means of a high speed stirrer a solution of 1 part by weight of colour coupler in 3 parts by volume of ethyl acetate into the aqueous gelatin at 55C in the presence of sodium dodecyl benzene sulphonate as dispersing agent followed by removal of the ethyl acetate by evaporation under reduced pressure.

The dispersion of colour coupler 7 in aqueous gelatin was then admixed with a positive redsensitized silver chloride emulsion, which comprised per kg g of gelatin and an amount of silver halide equivalent to 86 g of silver nitrate, in such an amount that after coating 1.92 g of colour coupler 7 was present per sq.m.

After exposure and colour-processing using Z-amino- S-diethylaminotoluene hydrochloride as colour developing agent a cyan dyestuff image having an absorption maximum of 702 nm was obtained.

EXAMPLE 2 Two positive red-sensitized silver halide emulsions were prepared as described in example 1 with the difference that instead of colour coupler 7, colour couplers 1 and 5 respectively were used. These colour couplers were incorporated into the emulsion from dispersions in aqueous gelatin, prepared as described in example 1, so that after coating on a support 1.88 g of Dyestuff image colour coupler l and 1.60 g of colour coupler respectively were present per sq.m.

After exposure and colour processing using Z-amino- S-diethylaminotoluene hydrochloride as colour developing agent cyan images were obtained having absorption maxima of 696 nm and 699 nm respectively.

The cyan dyestuff images formed had a favourable resistance to heat which is clearly apparent from the table below, in which the loss in density is given of the cyan dyestuff images formed with the above colour couplers as compared with the loss in density of a cyan dyestuff image formed in a similar way using N-nhexadecyl-1hydroxy-4-chloro-2-naphthamide as colour coupler. The loss in density is on a percentage basis measured at density D 1.5 after storing for 24 hours at 95C under a reduced pressure of less than 1 mm. Table Percentage loss in density measured at density D 1.5

Comparison dyestuff image Dyestuff image from colour coupler l Dyestuff image from colour coupler 5 EXAMPLE 3 A series of three silver bromoiodide emulsions (2.3 25

mole percent of iodide) each comprising per kg an amount of silver halide equivalent to 47 g of silver nitrate and 73.4 g of gelatin was prepared.

To each of the emulsions one of the following colour couplers were added in an amount of 0.006 mole per kg colour coupler 6, colour coupler l 1 and N-nhexadecyl-lhydroxy-4chloro-Z-naphthamide as comparison colour coupler. For this purpose the colour couplers were dissolved in ethyl acetate, the solutions formed dispersed in aqueous gelatin and the ethyl acetate removed under reduced pressure whereupon the gels obtained were admixed to the emulsions.

After dilution, adjustment of the pH and the addition of the usual additives such as hardening agents and wetting agents, the emulsions were coated on subbed cellulose triacetate supports and dried.

The materials formed were exposed for 1/20 sec. through a continuous wedge with constant 0.30 and developed for 8 min. at 20C in a developing bath of the following composition N,N-diethyl-p'phenylene diamine sulphate 2.75 g hydroxylamine sulphate 1.2 g sodium hexametaphosphate 4 g anhydrous sodium sulphite 2 g anhydrous potassium carbonate 75 g potassium bromide 2 5 g water to make l000 ml After development the materials were treated for 2 min. at l820C in an intermediate bath comprising 30 g of sodium sulphate in 1 litre of water.

The materials were rinsed for 15 min. with water and then treated in a bleach bath of the following composition borax 20 g anhydrous potassium bromide 15 g anhydrous sodium bisulphate 4.2 g potassium hexacyanoferrateflll) 100 g water to make 1000 ml After bleaching the materials were rinsed with water for 5 min. and fixed in an aqueous solution of 200 g of sodium thiosulphate per litre.

After a final rinsing for 15 min. the materials were dried.

The cyan dyestuff images formed were then examined as to their resistance to heat as described in example 2. The results attained are listed in the following table.

TABLE Colour coupler used Percentage loss in density comparison colour coupler 64 colour coupler 6 6 colour coupler l l 6 We claim: 1. Photographic element comprising a light-sensitive silver halide emulsion and a colour coupler having the following general formula:

| 1 20 --CONH-&R3

wherein:

Z represents the atoms necessary to close a fused-on benzene or tetrahydrobenzene ring,

Y represents hydrogen, halogen, or sulpho in acid or salt form, azo, or SR wherein R stands for alkyl or aryl,

R represents a straight-chain C -C alkyl group or an halogen-substituted aryl group,

R represents a straight-chain C -C alkyl group, or R together with R represent the atoms necessary to close a cycloaliphatic ring, and

R stands for a diffusion-fast making group comprising from 10 to about 20 carbon atoms in a straight alkyl chain, or R together with R represent the atoms necessary to complete a diffusion-fast making cyclo-aliphatic hydrocarbon group which comprises in the ring or together with the C-atoms of an alkyl substituent on the ring at least 12 C-atoms.

2. A photographic element according to claim 1, wherein in the formula of the colour coupler R stands for alkyl with from 10 to about 20 C-atoms.

3. A photographic element according to claim 1, wherein in the formula of the colour coupler R stands for the group -X,-D wherein D is an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X stands for COO, CON(R V. 7 Yr Y1, or oomm-Q R being hydrogen or C C alkyl and Y being a chemical bond, oxygen, sulphur, sulphonyl, NHCO, CONl-l, NHSO or SO,NH.

5. Photographic element according to claim 1 wherein said element is a multilayer colour material comprising in one of the light-sensitive silver halide emulsion layers or in a non-light-sensitive waterpermeable colloid layer in water-permeable relationship with the light-sensitive silver halide emulsion layer the said colour coupler.

6. Process of producing a cyan dyestuff image by development of a photographic element containing imagewise exposed silver halide with the aid of a primary aromatic amino developer in the presence of a cyanforming colour coupler corresponding to the formula:

R1 CONH+R3 wherein:

Z represents the atoms necessary to close a fused-on benzene or tetrahydrobenzene ring,

Y represents hydrogen, halogen, or sulpho in acid or salt form, azo, or SR wherein R stands for alkyl or aryl,

R represents a straight-chain C C alkyl group or an halogen-substituted aryl group,

R represents a straight-chain C C alkyl group, or

R together with R represent the atoms necessary to close a cycloaliphatic ring, and

R stands for a diffusion-fast making group comprising from 10 to about 20 carbon atoms in a straight alkyl chain, or R together with R represent the atoms necessary to complete a diffusion-fast mak ing cyclo-aliphatic hydrocarbon group which comprises in the ring or together with the C-atoms of an alkyl substituent on the ring at least 12 C-atoms.

7. The process of claim 6 wherein R stands for alkyl with from 10 to about 20 carbon atoms.

8. The process of claim 6 wherein R stands for the group -X,-D wherein D is an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X stands for --COO, CON(R wherein R is hydrogen or C C alkyl and Y is a chemical bond, oxygen, sulphur, sulphonyl, NHCO, CONH, NHSO or SO Nl-l.

9. The process of claim 6 wherein R stands for the group Cl-l X D wherein D is. an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X stands for N(R sulphur, -COO-, 4)-

R being hydrogen or C C alkyl and Y being a chemical bond, oxygen, sulphur, sulphonyl, NHCO, CONH, NHSO or SO NH.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,752,921 Dated October 2,' 1973 Invent0r(s) Hector Alfons VANDEN EYNDE ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

I In the heading, [30] Foreign Application Priority Data, the priority claim should appear asfollows:

Feb 24, 1970 Great Britain sass/705. Column 4, lines 1 7, Formula 3, the formula should appear as follows:

a. f l0H C 7 I I I -a- "CONH c (CI-I CH I I 3113 50 K Column 5, line 52, after 'YThen" insert a comma Column 8,line 61; fitered" should read filtered Columnl l, line 10, "halid" should read halide I Column 18, lines 31 5'33, claim 9, second formula, the formula'should appear as follows: I

I I I Y1 CO 4.

Signed and sealed this 17th dayof oeptember l974i (SEAL);

Attest: I

McCOY M. GIBSON C. MARSHLL DANN' I Attesting Officer 7 I ComissionerpflPatents FORM Po-wso (10-69) I V I "C b 5 w u.s. Govnunrni' unique oinc: 1p" p-au-u'f 

2. A photographic element according to claim 1, wherein in the formula of the colour coupler R3 stands for alkyl with from 10 to about 20 C-atoms.
 3. A photographic element according to claim 1, wherein in the formula of the colour coupler R3 stands for the group -X1-D wherein D is an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X1 stands for -COO-, -CON(R4)-,
 4. A photographic element according to claim 1, wherein in the formula of the colour coupler R3 stands for the group -CH2-X2-D wherein D is an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X2 stands for -N(R4)-, sulphur, -COO-, -CON(R4)-,
 5. Photographic element according to claim 1 wherein said element is a multilayer colour material comprising in one of the light-sensitive silver halide emulsion layers or in a non-light-sensitive water-permeable colloid layer in water-permeable relationship with the light-sensitive silver halide emulsion layer the said colour coupler.
 6. Process of producing a cyan dyestuff image by development of a photographic element containing imagewise exposed silver halide with the aid of a primary aromatic amino developer in the presence of a cyan-forming colour coupler corresponding to the formula:
 7. The process of claim 6 wherein R3 stands for alkyl with from 10 to about 20 carbon atoms.
 8. The process of claim 6 wherein R3 stands for the group -X1-D wherein D is an acyclic aliphatic hydrocarbon group having from 10 to about 20 carbon atoms and X1 stands for -COO-, -CON(R4)-,
 9. The process of claim 6 wherein R3 stands for the group -CH2-X2-D wherein D is an acyclic aliphatic hYdrocarbon group having from 10 to about 20 carbon atoms and X2 stands for -N(R4)-, sulphur, -COO-, -CON(R4)-, 